Introduce computer hardware and computer system parts with input output devices. Free computer system ebooks and ppt.

1. BIT
Computer Systems
Overview of Computer Systems
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2. What is a Computer…?
• Man-made, programmable electronic machine that can store,
retrieve, and process data according to a given set of
instructions
• Simply we can say ‘It is electronic/intelligent device which can
convert raw DATA in to meaningful INFORMATION ’
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3. DATA
• Data can be defined as ‘Raw facts’, ’Meaning less
things’ or ‘Un-processed things’
• Normally data can be input to a system.
• E.g.- In an organization: employee’s name, number of
hours of work, employee address, and employment
commenced date, etc
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4. INFORMATION
• Processed data and which has a meaning
unlike data.
• Normally Information are output from a
system.
• E.g.-In an organization: monthly salary of an
employee, total sales in a particular month,
etc
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5. Total Computer System
• A system is a collection of elements that work together to
achieve a common objective.
Total
Computer
System
Hardware Software Liveware
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6. Total Computer
System
Hardware Software Liveware
System Software Application Software
Packages
Languages
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7. Computer Hardware
• The physical components (tangible parts) of a
computer known as Hardware.
• E.g.- System unit, Mouse, Keyboard, Monitor
etc 7
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8. Software
• Collection of programs or applications, which
contain the instructions that makes the
computer work.
• E.g.-
Windows XP, Ms-Word, Java, AVG, Virus,
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9. Liveware
• The computer users are known as Liveware.
• It can be anyone who use the computer.
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10. Hardware categorization
• Mainly computer Hardware can be
categorized as follows,
– Processor/CPU
– Memory & integrating devices
– Input devices
– Output devices
– Storage devices
– Communication devices
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11. Processor/CPU
• Can be defined as the ‘Brain’ of the computer.
• All the commands are execute from here.
• Mainly consists with two parts,
»ALU
»CU
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12. ALU-Arithmetic & Logic Unit
• Responsible for performing Arithmetic
functions such as,
– Addition (+)
– Subtraction (-)
– Division(/)
– Multiplication(*)
• And Logical functions like,
– Is Greater than (>)
– Is Less than(<)
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13. CU-Control Unit
• Responsible for controlling all the Hardware of
the computer and all the Software of the
computer.
• All tasks of the computer has been runs under
the direct co-ordinations of CU.
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14. Memory
• There are two types of memories within
computer,
– RAM (Random Access Memory)
– ROM (Read Only Memory)
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15. RAM
• Random Access Memory.
• The currently processing data are held within
the RAM.
• Measures as a capacity. (MB,GB)
• Temporary, Volatile.
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16. ROM
• Read Only Memory.
• If Compare with the RAM has low capacity.
(Measures with KBs)
• Contain a special software called ‘Firmware’, which
use to turn on the computer (booting) properly by
recognizing the Hardware devices at the system
start-up.
• Firmware also known as ‘BIOS’, Start-up program,
‘CMOS’ setup.
• Non-volatile, Permanent memory type
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17. Storage Devices
• The memory locations where use to store
Data/Information permanently.
• E.g.
– HDD (Hard Disk Drive)
– CD-ROM
– DVD-ROM
– Tape Drive
• Much large in capacities. (Measures by using
MBs or GBs)
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18. Communication Devices
• Hardware devices use for the communication
purposes.
• E.g.
– MODEM
– Router
– Switch/Hub
– Repeater
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